The present invention relates to conveyor pushers. More particularly, the present invention relates to a pusher assembly mounted on the underside of a roller conveyor.
Package delivery companies pick up millions of packages daily from thousands of locations over a large geographical area and transport them to sorting facilities, primarily by truck and airplane, so they can be routed to a correspondingly large number of scattered destinations. To meet a rigorous schedule and provide accurate deliveries, a package delivery company must use automated transfer systems in the sorting facilities to match incoming packages with proper outgoing transport headed for the packages"" destinations. Because deliveries are time sensitive, the sorting equipment must be very fast, yet provide gentle and accurate handling of packages.
Belt and roller conveyor systems have often been used in package sorting systems to move packages from incoming loading docks to outgoing transport. An initial sorting of packages traveling along a conveyor may be accomplished by diverting packages from the conveyor based on their destinations, or based on their size or another characteristic.
To automate handling of articles traveling on conveyor systems, conveyor diverter assemblies of various types have been developed. Several systems have been developed to push articles off conveyors with pushing arms that sweep directly across the conveyors. Examples of such systems are shown in U.S. Pat. Nos. 3,026,988, 4,295,559, and 4,732,260. These pushers generally mount over or on the side of the conveyor. The pushers also often require special guarding to protect operators from the moving pusher. Both of these characteristics generally limit access to the conveyor.
The present invention relates to an article pusher assembly for use with a roller conveyor having a plurality of parallel rollers that define a conveying surface having opposed sides at a given distance. The pusher assembly generally comprises a carriage assembly adapted to be mounted under the conveying surface. A pusher blade is adapted to be positioned such that a portion thereof is generally above the conveying surface and at least one portion extends between a pair of adjacent rollers and connects to the carriage assembly. A drive unit is adapted to be mounted under the conveying surface and to selectively drive the carriage assembly.
The carriage assembly preferably includes first and second carriages. A multiplier unit interconnects the first and second carriages and is configured to move the first carriage relative to the second carriage in direct relation to movement of the second carriage. The preferred carriage assembly further includes a biasing member positioned between the carriage and the pusher blade such that the pusher blade is generally maintained in, but deflectable from, a plane parallel to the conveying surface.